Safety relief-valve



(No Model.)

A.- D. KILBORN. SAFETY RELIEF VALVE.

, /////////fl////////M Patented Jul 15, 1890.

UNITED l STATES PATENT OFFICE.

ALDEN D. KILBORN, OF OAK LAND, CALIFORNIA.

SAFETY RELIEF-=VALVE.

SPECIFICATION forming part of Letters Patent No. 432,140, dated July 15, 1890.

Application filed March 21, 1890.

To all whom it may concern:

Be it known that I, ALDEN D. KILBORN, a citizen of the United States, residing at Oak-. land, Alameda county, State of California, have invented an Improvement in Safety Relief-Valves; and I hereby declare the following to be a full, clear, and exact description of the same.

My invention relates to certain improvemen ts in safety relief-valves; and it consists in the combination, with the safety-valve casing, cup-shaped adjusting end, and tensionspring, of a valve and valve-scat having expansion chambers or grooves formed in the meeting faces thereof.

Referring to the accompanying drawings for a more complete explanation of my invention, Figure 1 is a vertical section taken through my valveapparatus. Fig. 2 is an enlarged perspective view of the valve, show ing the expansion-chamber. Fig. 3 is a similar view of the valve-seat, showing the corresponding chamber in it. Fig. 4 is an enlarged section of one end of the valve and of its seat.

A is the base, upon the upper end of which the valve-seat is formed and to which the shell or casing B is attached by screw-thre ads, so that it may be easily removed at anytime from the base without disturbing the latter. \Vithin this casing is contained the valve 0, which is acted upon and kept closed by the spring (3, and the tension of this spring is regulated by means of the cup-shaped nut D, fitting into the upper end of the casing and adjustable therein, as shown in my former patent, dated March 27, 1883, No. 274,787.

My present invention is an improvement upon the valve shown in said patent, and it consists in forming the valve 0 with a fiat face at around the inner portion, which is adapted to close upon a corresponding flat or horizontal seat I) on the base A. Around the seat I) is formed a V-shaped groove orchannel 0, having exterior to it an upwardly-projecting lip or flange cl. Around the valve-face is formed a channel or groove 6, which is wide enough to cover the groove or channelin the Serial No- 3 i4,803. (No model.

valve-seat, and also to inclose the upwardlyprojecting lip or flange cl, which surrounds this groove or channel. Outside this channel 6 of the valve is a downwardly-projecting lip or flange f, which extends downwardly around the lip or flange d of the valve-seat.

The upwardly-projecting flange cl on the valve-scat is a little higher than the seat itself, while the downwardly-projecting lip 01' flange f, which surrounds the valve-face, is a little deeper or lower than the valve-face itself, so that these two form steps, as it were. The object of these grooves or channels is to form around the valve-seat and around the face of the valve which fits upon said seat an expansion-chamber, into which the steam is first admitted when the valve begins to rise on account of the pressure below overcoming the tension of the spring, and the expansion of the steam within this chamber immediately raises the valve, and as the steam escapes be tween the valve-face and the valve-seat the expansion within the chambers thus formed lifts the valve suddenly, by reason of the eX terior flange, so as to open it to a considerable distance and allow a free escape for the steam within the casing C. This escape-opening is made much larger on account of the expansion-chambers than any opening which is formed by simply lifting the ordinary conically-seated valve, and the boiler may thus be relieved of its surplus pressure in very short time, so that the valve will close again immediately.

By forming the groove in the valve-seat V shape a practically sharp knife-edge is prod need by the upwardly-proj ectin g lip or flange (Z. The action of this lip is to cut the steam off sharply and abruptly as soon as the pressure has decreased sufficiently to allow the valve to begin to close.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

The improvement in safety-valves, consisting of a flat valve-seat having the surrounding V-shaped groove or channel, and the upwardly-projecting A-shaped flange forming a sharp edge around said channel, in connecand outside of the A-shaped flange of the tion with a Valve having a flat face fitting valve-seat, substantially as described. 10 upon the interior flat seat, a groove or chan- In witness whereof I have hereunto set my nel formed around said face and acting in hand.

conjunction with the V-shaped groove in the ALDEN D. KILBORN. valve-seat to form an expansion-chamber Witnesses:

around said seat, and an exterior annular GEO. H. STRONG,

flange projecting downwardly from the Valve S. H. NOURsE. 

